Rotary pump



Patented July l0, 1928.

UNITED STATES PATENT l OFFICE.

RUBEIRJJv W. KING, 0F TORONTO, ONTABIQ, CANADA.

ROTARY PUMP.

Application ledotober 11, 1926. Serial No. 141,004.

sliding blades is eccentrically mounted in a stationary casinor or cylinder, ,and the cylinder is provided` with a perforated barrel adapted to rotate with the piston. I-Iitherto the said barrels have been' mounted concentrically in the pump casings and have not been so' arranged as to automatically take up wear.

The object of my invention is to construct a device of the kindy described, which is highly efficient, silent,of cheap and Vsimple construction, easily adjusted or repaired and which will retain these features when made in the s-maller sizes. Other objects I have in mind will hereinafter appear.

Improved means for lubricating the pump is also provided. i

An' adjustable bearing is provided for receiving end press-ure of driving shaft of the pump. Y

My invention is hereinafter more fully de? scribed and illustrated in the accompanying drawings in which F ig. 1 is a cross section of my improved pump;

Fig. 2 is a longitudlnal section of the same;

Fig. 3 'is a plan view of part of the ring and casing; and l Fig. 4 a plan View of shaft end bearing.

In the drawings like numerals of reference indicate corresponding parts in the different figures. i Y

The pump comprises the casing cage or cylinder a, supporting an eccentrically mounted driving shaftb, rotated by means not shown, a piston C attached to the shaft and containing a series of sliding blades G, and the ring z'. The latter surrounds the piston and blades.

The casing a has suitable removable covers aand has opposing suction and compression chambers g and h. These chambers open to the interior ofthe casing and are comparatively narrow relative to the entire width of the casing, and are respectively connected to the entrance and exit ports g and h of the pump.

The piston C, suitably connected to the driving shaft b, is provided 'with a centrally. located chamber Z which communicates with the channels in which the blades slide. The said chamber is of such a diameter that' in the process of machining the channels they will connect with thevchamber and one another through-the chamber without further machining being required. In pumps of this nature when sliding blades are used, and especially when blades of thick fibre, of less4 specific gravity than comparatively thin blades of iron or steel are used, it is important that no hindrance to their free action will occur. When the channels for the blades are cut into a solid piston the blades have to expel the fluid as they enter the channels, and are hindered by -suction as they leave. The construction described overcomes this diiiculty as thereby the pressure in the fluid spaces and consequently in the channels remains substantially constant because as so'on as some blades are advancing a like number arereceding. This construction also facilitates the lubrication of the blades in a manner hereinafter described.

The ring z' is loosely fitted in and unjourna-lled concentrically with the casing a, and is free to move in any direction within the limits of its` cage to find its natural position on the interior of the casing. v The ring thus advances and maintains contact with the hereinafter described parts of the casing as Wear takes place. The ring is caused to revolve by its frictional contact with the blades. `The central portion only of the periphery of the ring is liberally perforated so that when in place in the cylinder a, its perforati'ons 12 are opposite Vthe chambered portions ofthe casing. The imperforated end portions of the ring` form liberal Wearing surfaces to contact with the unchambered portions of the interior of the casing.

It is essentialto the life of the pump that the'ring' be accurately machined to a true circle smoothly polished on its outside periphery, be accurately balanced and be free to locate itself in the casing.- There are two locations, only, in the inner periphery of the casing where it is necessary for the ring to contact in order to form stops to prevent or minimize the escape of the fluid from the compression to the suction side of the pump.

These stops and K are located between the suction and com ression chambersg and k.

The ring i tends y means of the pressure ofthe fluid passing therethrough to contact with these stops in' the same manner as a valve to its seat. The pressure, due tol theA ow of fluid, is maintained low enough to permit of the' free rotation of the ring, while sufficient to checkthe back flow referred to,

'enters the suction port.

by suitably proportioning the perforations of the ring.

The stop portion K extends through 'an arc'of greater length than the length of the arc between the adjacent blades G so that it will close all the perfor-ations l2 between the blades contacting with the ring beneath the stop portion whereby the fluid under com pression cannot pass through the said perforations toescapc from the compression to the suction sides of the pump.

The stop portions j and K are preferably made with a shell construction lled with anti-friction metal formed therein in any suitable manner While in place on the ring or on a ring standard specially prepared for that purpose. Thus an accurate lit to the actual periphery of the ring is obtained at minimum expense.

The piston C is ymachined substantially smaller in outside diameter than the inside diameter of the. ring to prevent contact therewith. Y

When an air compressor pump is directly connected to an electric motor the speed at which it is driven is predetermined and unalterable according to the' nature of the electric current employed. The should be designed to compress the maximum amount et air at the maximum pressure likely to be required with a margin to allow for the usual lossl of air in this type of pump. When the full pressure @fair is not required, a common practice is to reduce the supply by means of a valvein the supply pipe and permit the unused portion of the compressed air to return b suitable passageways to the suction'side o the pump. This air is then recompressed along` with the new air that The pumpv and motor are thus operated at full capacity at allv times which reduces the efciency of both, thus increasing the cost of upkeep and it also' wastes electric energy. To overcome these objectionable features Iprovide a bypass l having a valve 1 and forming a communication between the compression chamber t and the interior of the ring at 2. The point 2 is so located that the air in the pockets formed bythe blades G, ring 'i and piston C will not be fully compressed. When the valve 1 is opened all the air at a reduced pressure passes from the pockets.

The pump parts are lubricated as'follows. An oil reservoir, not shown, is situated so that the level of the oil'is below the bottom of the pump so that oil cannot flow when the pump is at rest. Suitable pipes or tubes, not shown, connect vthe bottom of the oil reservoir withv the combination needle valve and sight feed fittings 6, and 6', from which the oil is conductedby Apipes or tubes to the journals of the pump. Suitable-passages 21 and 21 carry the oil round the journals and these grooves communicatewith Pump revolving the piston, causes the oil to be drawn from the reservoir through the fitting 6 to the passages 2l for lubricating the main bearing p. rl`he oil is then drawn through the conduit ll into the said expanding pockets where it lubricates the sliding blades G. y The most important wearing parts are thus first oiled while the oil is cool and in liquid form. Oil also passes through the perforations. in the ring to lubricate it and any sediment or heavy condensed oil passing into the compression chamber h will bc directed downwardly by the 'baille el into the lower part of the chamber. A drain pipe 5 is adapted to drain the lower part of the chainber. Some of the oil drawn into the pockets will be forced, when the air is compressed in the pockets, along the blades G into the chamber Z. This chamber communicates by means of passages m and 'a with the thrust bearing o which is carried by the bearing p. The passage 21 communicates with the passage 'a whereby the outboard bearing` p is lubricated. lf it is desired this bearing p 'may be lubricated with fresh oil by opening the valve in the fitting which controls the flow ofvoil through the conduits 2l', ll', and 9', and thus ultimately to the chamber C.

In myv description l'. have described the pump for use in pumping air. lt should be understood, however, that the construction described is equally applicable for use with other fluids and that modifications, especially in the relative posit-ions and directions of the inlet and outlet ports, maybe made in the construction without departing from the spirit of my invention. Y

lVhat l claim is:

1. A rotaryengine or pump comprising a cylinder casing; a rotary piston eccentric to the cylinder;V a plurality pf blades slidable Vin 'the piston; suction and compression chambers formed at opposite sides of the cylinder andV of less width than that of the cylinder; and an unjournalled floating ring of the full Width of the cylinder and interposed between the cylinder and piston, the ring being free to rotate with the piston and blades and havingperforations located only intermediate the ends thereof for com-` munication withl the suction and compression chambers, the area of the perforations being proportioned to cause a frictional pressure of the ring against the casing, due to the flow lof fluid, less than the frictional driving pressure of the blades against the ring. j

2. A rotary engine or pump comprising a cylinder casing; a rotary piston eccentric to the cylinder; a plurality of blades slidable in the piston; suction and compression chambers formed at opposite sides of the c linder and of less width than that of the cy inder; an unjournalled floating ring of the full width of the c linder and interposed between the cylin er and piston, the ring being free to rotate with the piston and blades' and having perforations located onlyintermediate the ends thereof for communication with the suction and compression chambers; and a replaceable stop for engaging the ring to prevent the escape of fluid from the compression tov the suction chambers, ysuction chamber and stop being positioned so that the How of fluid towards the compression chamber has a tendency to force the ring against the said stop, the area of the perforations being proportioned to cause a frictional pressure of the ring against the stop, due to. the How of fluid, less than the frictional driving pressure of the blades against the ring.

3. A rotary engine or pump comprising a cylinder casing; a rotary piston eccentric to the cylinder; a plurality of blades slidable in the piston; suction and compression chambers formed at opposite sides of the cylinder and of less Width than that of the cylinder; an unjournalled floating ring of the full width of the cylinder and interposed between the cylinder and piston, the ring being free to rotate with the piston and blades and having perforations located intermediate the ends thereof for communication with the suction and compression chambers; and two stops for-engaging the ring to prevent the escape of fluid vfrom the compression to the suction chambers located at the compression side of the device, suction chamber and stop being positioned so' that the liow of vfluid towards the compression chamber has a tendency to force the ring against the said stops, one of the said stops being adjustably carried in the casing.

4. A rotary engine or pump comprising a cylinder casing; a rotary piston eccentric to the cylinder; a plurality of blades slidable in the piston; suction and compression chambers formed at opposite sides of the cylinder and of less width than that of the cylinder; an unjournalled floating ring of the full width of ythe cylinder and interposed between the cylinder and piston, the ring being free to rotate with the piston and blades and having perforations located only intermediate the ends thereof for communication with the suction and compression chambers; and two adjustable stops for engaging'the ring to prevent the escape of fluid from the compression to the suction chambers located at the compression sidev of the device, and so positioned in relation to the interior of the cylinder and to the outer periphery of the ring member that the fluid passing to the discharge tends to force the ring into contact with the stop members.

5. A rotary pump comprising a cylinder having an inlet yand anoutlet and suction and compression chambers; a piston -eccentric to the cylinder; a plurality of blades slidable in the piston; a. loosely fitted ring 4interposed between the cylinderand piston land provided with perforations; means for preventing leakage from the pressure side of the device to the suction side; a conduit forming a communication between the compression chamber and the interior of the ring whereby air under lowpressure may be de.- livered to the compression chamber; and a valve in said conduit.

6. A rotary engine orpump including a cylindrical casing; a piston journalled in the casingl provided with a plurality ofslid-4 ing blades and forming expanding and contracting pockets therebetween; an oil supply a conduit communicating with the pockets when expanding, whereby the oil is sucked forming contracting and expanding pockets therebetween; a chamber in the piston adapted to receive the inner ends of the sliding blades; an oil supply; conduits connecting the oil supply with the interior of the pockets when expanding, the resulting pressure in the pockets when contracting forcing oil along the sliding blades into the chamber; and conduits connecting the said chambcrwith the interior cf the said pockets when expanding.

9. A rotary engine or pump of the class described containing a piston mounted on a shaft journalled in -the casing; a chamber in the piston; oil conduits to the chamber from the suction side of the piston; an end thrust bearing for the shaft; and a conduit from the chamber to the thrust bearing, whereby the same may be lubricated by oil from the chamber.

10. A rotary engine or pump of the class 'described containing a piston mounted on a shaft journalled in the casing; a chamber in the piston; oil conduits to the chamber from the suction side of the piston; an end thrust bearing for the shaft; and a conduit from the chamber to the thrust bearing, whereby the same may be lubricated by oil from lthe chamber; a connecting conduit with the original oil supply whereby both lll outlet ports; a rotary the outer journal and end bearing can be lubricated with fresh liquid oil if desired; and conduits connecting said last mentioned conduit with the suction side of the piston.

ll. A rotary engine or pump comprising a cylinder' casing; a rotary piston eccentric to the cylinder; a plurality of blades slide-ble in the piston; inlet and outlet ports at opposite sides of the cylinder; an unjournalled llo-ating ring interposed between the cylinder and pist-on, thevring being loose in the cylinder and free to rotate with the pistou and blades; and two stop portions on the interior periphery of the cylinder adjacent opposite sides of and opposite the inlet port and the outlet port into contact with which the ring is lifted by the pressure of the lluid passing through the engine or pump.

l2. A rotary engine or pump comprising a cylinder casing having opposite inlet and piston eccentric to the cylinder having at least. three slidable bladesj an unjournaled loosely fitted perforated ring of anexternal diameter substantially smaller than the internal diameter of the casing free to rotate with the piston and blades and arranged to seat against the casing at the outlet side thereof, whereby, when. the piston is rotated at high velocity, a current of air or other fluid passing through the casing from the inlet tothe out- Y let will compel the ring to locateitself opposite the exit forming with the casing an obstruction so that -only the Huid passing through the perorations made inthe ring will be discharged at the exit..

13. A rotary engine or pump comprising a y perforations located intermediate the ends thereof for communication with the suction and compression chanil'iers, whereby, when the piston is rotated at high velocity, the induced current of iluid passing through the casing from the inlet to the outlet will cause the ring to float and seat itself in a position obstructing the discharge of fluid from the cylinder so that only the fluid compressed in its passage through the 'ring will be discharged'at the exit from the cylinder.

14. A rotary engine or pump including a casing; a piston journalled in the casing provided with a plurality of sliding blades forming contracting and expanding pockets therebetween; a chamber in the piston adapted to receive the innerends of the sliding. blades; an oil supply; and conduits connecting the oil supply with the ,interior of the pockets when expanding, the resulting pressure in the pockets when contracting forcing oil along the sliding chamber.

Signed at Toronto,.Canada, this 25th day' of September, 1926.

1 p ROBERT W. KING'.

blades' into the' 70 

